3. References used to establish traceability

First and foremost, the reader is reminded that traceability should not be confused with accuracy and precision, which cover, respectively, the closeness of agreement between the "true value" (corresponding to the value that would be obtained by measurement if the quantity could be completely defined ) and the measured value, and the closeness of agreement between the results obtained by the same experimental procedure repeated several times under prescribed conditions. The general aspects of quality assurance in environmental monitoring programs (including accuracy and precision) have been described in detail in the literature...